Escrow?
With so many accounts bought and sold, would be risky, but if someone interested would like to escrow that is well known then there are no problems with that.
You should contact well known escrows. With a brand new account and with that statement that only compiled windows binary will be provided resembles very much with a cheap scam where you will post here a walletbuilders compilled free coin because they do not provide source for free coins only windows binary.
Nothing about the coin is a scam. Source will be provided after the goal has been reached. Halo 2 is a Microsoft game.
Is Microsoft in on this?
Almost certainly not, Microsoft's video game rights, licensing or franchising is extremely expensive. The dev can't probably afford it.
Halo 2 is a Microsoft game